What are the three main sources of new words in present-day Engl

What are the three main sources of new words in present-day English vocabulary? Match the following expressions with the three sources as examples.
“green revolution”，“fast food’’，“the fourth world”，“Mao jackets”，“open heart surgery ”
【正确答案】：Generally, there are three main sourcesof new words:
The rapid development of modern science and technology, e.g. green revolution open heart surgery.
Social, economic and political changes, e.g. fast food, the fourth world.
The influence of other eultures and languages, e.g. Mao jackets.